I think life circumstance plays as much of a role as raw talent. As distance running becomes a more respected sport and thus draws more talented athletes, and the physiology of what makes a great distance athlete and the training needed to do so becomes clearer we see more and more sub 4:00 milers emerge.
Im 22 and i’ve seen sub 4:00 go from a pro standard that was rare for college athletes and unheard of for highschool athletes to something that a handful of college athletes could do yearly and highschool athletes could occasionally do to 4:00 just about becoming the standard for “good” in college and a yearly requirement to be the best in a competitive state at the HS level.
I got to the level where I was almost smelling it in college, I had the prerequisite speed and some, could hang with competitive D1 XC guys, and ran a few workouts that would’ve been considered predictors. I think I could’ve been a pro miler instead of a pretty good 400/800 guy under different circumstances, I was overweight until I was 16, didn’t have visible abs until I was 18, and my training consisted of being a middle linebacker/tight end at a crappy highschool program from the age of 11 until I was 16. I guarantee you that was the cause of injury proneness and injuries to my body that probably left small residual dents in my running potential. By the end of my freshman year, I was worse than average on my mediocre XC team, I wanted to break 20:00 in the 5k by the end of highschool by the end of that year. By the end of senior year I was beating the whole team 400m-5k and was the 4th distance boy in team history to end up on a college roster. The 3rd kid has a Nike contract and has worn a team USA singlet. He set the school 3200m record his freshman year. If I grew up with the Ingebrigsten treatment, I’m not saying i’d be a worldbeater by any means but I think you’d know my name. Imagine if I started highschool in 17:00 5k shape and ran for a good program instead of 30:00 at a program where a sub 17:00 effort puts you on the top 10 list. My childhood life choices and circumstance crushed my potential and I didn’t even realize it.
That being said, when I was a kid, I would win the mile or mile and a half at school despite jiggling while doing it. I would go running with my neighborhood run club that mostly consisted of adults 1-2 times a month and beat all of them but my dad (run club where everyone competed against eachother every run instead of running together), I would nuke my whole football team on conditioning days and not understand why they were all moaning and puking after 100yd sprints or ladders. After I left the team for running the team speed demon who was known statewide for superior speed got beat by me in a 200m during track season and I did a standing start. I did a half marathon off of 3-4 weeks of actual training earlier this summer and beat a field of 800ish people by over a minute. Many people who have been training for this specific race for months, consistent miles and a consistent diet. I could outlift anyone on my highschool track team during highschool let alone the distance kids.
All of this to say that many people would shock themselves if they explored their full potential, but you do need a special kind of talent to be a sub 4:00 miler. I haven’t broken 4:00 and I don’t know if it’s even in the cards for me and in the least narcissistic way possible I believe I have more talent for running a few laps around the track than over 99% of people. That being said I think that there are thousands of people in the US let alone the world that possess as much talent as I do and they are doing water polo or fortnite or making music or something and haven’t and never will run a mile under 5:00 let alone 4:00.